Krypton (Kr)
Krypton (Kr) is element 36 of the periodic table, a noble gas in period 4 and group 18. Its standard atomic weight is 83.798, so one mole of krypton atoms has a mass of 83.798 g. At room temperature it is a gas; it melts at -157.36 °C and boils at -153.22 °C.
| Atomic number | 36 |
|---|---|
| Symbol | Kr |
| Standard atomic weight | 83.798 |
| Molar mass | 83.798 g/mol |
| Category | Noble gas |
| Group | 18 |
| Period | 4 |
| Block | p-block |
| Electron configuration | [Ar] 4s2 3d10 4p6 |
| Oxidation states | 0 |
| Electronegativity (Pauling) | 3 |
| Atomic radius (van der Waals) | 202 pm |
| First ionisation energy | 14 eV (1350.8 kJ/mol) |
| Electron affinity | — |
| State at room temperature | Gas |
| Melting point | 115.79 K (-157.36 °C) |
| Boiling point | 119.93 K (-153.22 °C) |
| Density | 3.733 g/L |
| Discovered | 1898 |
Group 18
Calculate with Krypton
Atomic weight: IUPAC CIAAW standard atomic weight. Other properties: PubChem (U.S. National Library of Medicine, public domain). Values such as melting point and radius depend on how they were measured; check a data book for precise work.